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CBSE Guess > Papers > Important Questions > Class X > 2008 > Science > Science By :- Nagesh Kumar
Science - Metals and Non-Metals
- Why the reaction of metals with water, hydrogen and acid cannot be used to compare the reactivity of metals?
- Write the electron - dot structure for sodium and magnesium.
- Why do electrovalent compounds have high melting and boiling points?
- What are minerals?
- What do you understand by ores?
- Define activity series of metals.
- Which type of metals is found in Free State in the earth’s crust?
- Write two advantages and one limitation of using carbon as reducing agent in the metallurgy.
- What is the difference between Calcination and roasting?
- What happens when zinc is added to a solution of iron (II) sulphate? Write the chemical reaction.
- Write equation for the reaction of
- Calcium with water
- Potassium with water
- Zinc with dilute hydrochloric acid
- What is gangue?
- What do you understand by metallurgy?
- Name two metals which will displace hydrogen from dilute acid and two metals which will not.
- What is an alloy?
- What chemical process is used for obtaining a metal from its oxide?
- Define corrosion of metals? What is rust? How can be rusting prevented?
- What is chemical name and formula of limestone? What happens when limestone is strongly heated? Write the chemical equation involved. How can the presence of excess of CO2 be tested in a class room from the products formed?
- Give an example of a metal which -
- is the best conductor of heat
- is a poor conductor of heat
- Give two examples of metals which can be easily cut with a knife .
- Which gas is evolved when magnesium reacts with very dilute nitric acid? Write the equation involved.
- Explain why is sodium Kept immersed in kerosene oil?
- What do you understand by Aquaregia?
- In the electrolytic refining of a metal M, what would you take as the anode and the cathode?
- Represent the formation of MgO and Na2O by the transfer of electrons. Name the ions present in these compounds.
- Differentiate between metal and non – metals on the basis of their chemical properties.
- Explain why zinc metal can displace copper from copper sulphate solution but copper cannot displace zinc from zinc sulphate solution.
- Why are stainless steel cooking pans often given a copper outer bottom?
- Give two uses of Aluminium.
- State the major steps usually involved in the metallurgical processes. Name the chief ore of aluminium. Describe with a labelled diagram and with the necessary chemical equations, how aluminium is extracted from this ore.
- What do you understand by metals?
- Write a metal and a non metal which is liquid at room temperature.
- Define malleability.
- What are non-metals?
- Name a metal that is not corroded in air.
- What type of oxides is formed when non-metals combine with oxygen?